Solder processing device

ABSTRACT

A solder processing method according to one or more embodiments may include: sequentially supplying at least two solder pieces into a substantially tubular iron tip that is extended vertically, such that the at least two solder pieces are erected within the iron tip in such a manner that on the solder piece which is first supplied, the solder piece which is subsequently supplied rides; and heating the substantially tubular iron tip in a state where the at least two solder pieces are erected within the iron tip in such a manner that on the solder piece which is first supplied, the solder piece which is subsequently supplied rides, to melt the flux to be flown out from at least one of the at least two solder pieces to a space between an inner wall of the iron tip and the at least two solder pieces.

This application is a division of application Ser. No. 15/558,562, filedon Sep. 15, 2017, which is a national stage entry of InternationalApplication No. PCT/JP2016/058086, filed on Mar. 15, 2016, which claimspriority based on the Article 8 of Patent Cooperation Treaty from theprior Japanese Patent Application No. 2015-051573, filed on Mar. 16,2015, the entire contents of all of which are incorporated herein byreference.

TECHNICAL FIELD

The present invention relates to a solder processing device which heatsand melts a solder piece.

BACKGROUND ART

In recent years, electronic circuits on which electronic components aremounted have been incorporated in various types of devices. In a step offorming an electronic circuit, in order to perform, for example,processing for joining a lead wire to a wiring pattern (land) on aboard, soldering using a soldering iron is performed. In order tomechanically realize a soldering step, a solder processing device havinga portion of an iron tip is utilized.

For example, the solder processing device as described above isconfigured such that a solder piece (piece obtained by cutting a wiresolder in which a layer of a flux is provided within a solder layer) isheated in a posture where the solder piece is erected within the irontip and that thus the molten solder is supplied downward. In this way,it is possible to realize the soldering step on the board arrangedbelow.

RELATED ART DOCUMENT Patent Document

Patent Document 1: Japanese Unexamined Patent Application PublicationNo. 09-108826

Patent Document 2: Japanese Unexamined Patent Application PublicationNo. 2011-056581

Patent Document 3: Japanese Unexamined Patent Application PublicationNo. 2009-195938

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

When as described above, the solder piece is heated in the posture wherethe solder piece is erected within the iron tip, the flux having arelatively low melting point stats to flow out from the solder piece.When the flux appropriately flows out from the upper end or the sidesurface of the solder piece, the flux excellent in wettability isappropriately interposed between the inner wall of the iron tip and thesolder piece. Consequently, contactability between the inner wall of theiron tip and the solder piece is enhanced, and thus heat is sufficientlytransmitted from the iron tip to the solder piece, with the result thatit is possible to appropriately heat and melt the solder piece.

However, when the solder piece is heated in the posture where the solderpiece is erected within the iron tip, it is likely that the flux easilyflows out from the lower end of the solder piece. In this case, the fluxflows downward of the solder piece, and thus it is unlikely that theflux is interposed between the inner wall of the iron tip and the solderpiece.

Consequently, it is likely that heat is not sufficiently transmittedfrom the iron tip to the solder piece and that thus the solder piececannot be appropriately heated and melted. In view of the foregoingproblem, the present invention has an object to provide a solderprocessing device which can more reliably heat and melt a solder piecein a posture where the solder piece is erected within an iron tip.

Means for Solving the Problem

A solder processing device according to the present invention includes:a substantially tubular iron tip that can be heated and that is extendedvertically; and a solder piece supply portion that sequentiallysupplies, into the iron tip, a plurality of solder pieces in which alayer of a flux is provided within a tubular solder layer, within theiron tip, the solder pieces are erected such that on the solder piecewhich is first supplied, the solder piece which is subsequently suppliedrides and the heat of the iron tip is used to melt the solder piecessuch that the molten solder is supplied downward.

In this configuration, it is possible to more reliably heat and melt thesolder pieces in a posture where they are erected within the iron tip.

In the configuration described above, more specifically, the solderpiece supply portion may sequentially produce a first solder piece and asecond solder piece by cutting a wire solder, and supply the first andsecond solder pieces into the iron tip.

In the configuration described above, more specifically, the solderpiece supply portion may cut the wire solder such that the first solderpiece differs in length from the second solder piece.

In the configuration described above, more specifically, the solderprocessing device solders a terminal protruded upward to a board, andthe supply may be performed in a state where a tip end of the terminalenters the iron tip from below such that the first solder piece iserected on the tip end of the terminal.

In the configuration described above, more specifically, the solderpiece supply portion may cut the wire solder such that the second solderpiece is shorter than the first solder piece.

In the configuration described above, more specifically, within the irontip, a reception portion which receives the supplied first solder piecemay be provided, and the first solder piece may be erected on thereception portion. In the configuration described above, morespecifically, the reception portion may be protruded inward from theinner wall of the iron tip such that the inside diameter of the iron tipis smaller than the outside diameter of the first solder piece.

In the configuration described above, more specifically, the solderpiece supply portion may cut the wire solder such that the first solderpiece is shorter than the second solder piece.

In a solder processing method according to the present invention, aplurality of solder pieces in which a layer of a flux is provided withina tubular solder layer are sequentially supplied into a substantiallytubular iron tip that can be heated and that is extended vertically,within the iron tip, the solder pieces are erected such that on thesolder piece which is first supplied, the solder piece which issubsequently supplied rides and the heat of the iron tip is used to meltthe solder pieces such that the molten solder is supplied downward.

Advantages of the Invention

With the solder processing device according to the present invention, itis possible to more reliably heat and melt a solder piece in a posturewhere the solder piece is erected within an iron tip.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 A perspective view of an example of a soldering device accordingto an embodiment of the present invention;

FIG. 2 A cross-sectional view taken along line II-II in the solderingdevice shown in FIG. 1;

FIG. 3 An exploded perspective view of part of a drive mechanismprovided in the soldering device shown in FIG. 1;

FIG. 4 An illustrative diagram of a state where a first solder piece isheld within an iron tip in a first embodiment;

FIG. 5 An illustrative diagram of a state where first and second solderpieces are held within the iron tip in the first embodiment;

FIG. 6 An illustrative diagram of a case where the iron tip is heated inthe state shown in FIG. 5;

FIG. 7A An illustrative diagram for the supply and the heating andmelting of solder pieces according to a second embodiment;

FIG. 7B An illustrative diagram for the supply and the heating andmelting of solder pieces according to a second embodiment;

FIG. 7C An illustrative diagram for the supply and the heating andmelting of solder pieces according to a second embodiment;

FIG. 8 An illustrative diagram of a state where the first solder pieceis held within an iron tip in a third embodiment;

FIG. 9 An illustrative diagram of a state where first and second solderpieces are held within the iron tip in the third embodiment; and

FIG. 10 An illustrative diagram of a case where the iron tip is heatedin the state shown in FIG. 9.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention will be described below using, asexamples, first to third embodiments with reference to drawings. Thedetails of the present invention are not limited at all to theseembodiments.

1. First Embodiment

[Overall Configuration of Soldering Device]

FIG. 1 is a perspective view of a soldering device (one form of a solderprocessing device) according to the first embodiment, FIG. 2 is across-sectional view taken along line II-II in the soldering device Ashown in FIG. 1 and FIG. 3 is an exploded perspective view of part of adrive mechanism provided in the soldering device A shown in FIG. 1. InFIG. 1, parts of an enclosure and a support portion 1 are cut out, andthus the interior of the soldering device A is displayed.

As shown in FIG. 1, the soldering device A is a device in which a wiresolder W is supplied from above, and in which an iron tip 5 provided ina lower portion is utilized so as to solder a wiring board Bd arrangedbelow the iron tip 5 and an electronic component Ep. The wire solder Whas a structure in which a flux layer is provided within a tubularsolder layer. Hence, a solder piece produced by cutting the wire solderW likewise has the structure in which the flux layer is provided withinthe tubular solder layer. The soldering device A includes the supportportion 1, a cutter unit 2, the drive mechanism 3, a heater unit 4, theiron tip 5 and a solder feed mechanism 6. A combination of the heaterunit 4 and the iron tip 5 forms a soldering iron portion.

The support portion 1 includes a wall member 11 which is provided so asto stand and which is formed in the shape of a flat plate. In thefollowing description, for convenience, it is assumed that as shown inFIG. 1, a horizontal direction along the wall member 11 is an Xdirection, that a horizontal direction perpendicular to the wall member11 is a Y direction and that a vertical direction along the wall member11 is a Z direction. For example, as shown in FIG. 1, the wall member 11has a Z-X flat surface.

The soldering device A supplies molten solder to the wiring board Bdattached to a jig fixture Gj and a terminal P of the electroniccomponent Ep arranged on the wiring board Bd, and thereby connects andfixes them. When soldering is performed, the jig fixture Gj is moved inthe X direction and the Y direction so as to locate a land Ld on thewiring board Bd. Then, the soldering device A can be moved in the Zdirection, and after the location, the soldering device A is moved inthe Z direction, and thus it is possible to bring the tip end of theiron tip 5 into contact with the land Ld.

The support portion 1 includes: a holding portion 12 which is providedin a position displaced upward from a lower end portion of the wallmember 11 in the Z direction; a sliding guide 13 which is fixed to aside edge portion (lower portion) of the wall member 11 in the Zdirection; and a heater unit fixing portion 14 which is provided at anend portion (lower end portion) of the wall member 11 in the Zdirection.

The cutter unit 2 cuts the wire solder W fed by the solder feedmechanism 6 into a solder piece Wh which has a predetermined length.Although described in detail later, the soldering device A heats theiron tip 5 in a state where a first solder piece Wh1 and a second solderpiece Wh2 are supplied into the iron tip 5, and supplies the moltensolder downward. In the following description, the first solder pieceWh1 and the second solder piece Wh2 are collectively referred to as thesolder piece Wh.

The cutter unit 2 includes: a cutter lower blade 22 (fixed bladeportion) which is fixed to the sliding guide 13; a cutter upper blade 21(movable blade portion) which is arranged in an upper portion of thecutter lower blade 22 and which is arranged so as to be able to slide inthe X direction; and a pusher pin 23 (solder pushing portion) which isprovided in the cutter upper blade 21 and which slides in a direction (Zdirection) intersecting the direction of sliding of the cutter upperblade 21. As shown in FIG. 1, the movement of the cutter upper blade 21in the Z direction is restricted by the sliding guide 13, and the cutterupper blade 21 can slide in the X direction.

Here, the sliding guide 13 will be described in detail. The slidingguide 13 includes a pair of wall portions 131 which make contact withboth ends of the cutter lower blade 22 in the Y direction, and the pairof wall portions 131 include stopper portions 132 which are protrudedtoward the other side. In the stopper portions 132, tip ends areprevented from making contact with each other, and in other words, anopening is provided in an upper portion of the sliding guide 13. Thestopper portions 132 restrict the movement of the cutter upper blade 21in the Z direction.

As shown in FIG. 2, the cutter upper blade 21 includes an upper bladehole 211 that is a through hole into which the wire solder W fed by thesolder feed mechanism 6 is inserted and a pin hole 212 that is a throughhole into which the rod portion 231 of the pusher pin 23 is inserted.The side edge portion of the upper blade hole 211 at the lower end isformed in the shape of a cutting blade. The cutter lower blade 22includes a lower blade hole 221 that is a through hole into which thewire solder W passing through the upper blade hole 211 is inserted. Theside edge portion of the lower blade hole 221 at the upper end is formedin the shape of a cutting blade. In a state where the wire solder W isinserted into the upper blade hole 211 and the lower blade hole 221,they are displaced in a direction intersecting the wire solder W, andthus the wire solder W is cut by the cutting blades thereof.

The pusher pin 23 is the solder pushing portion, and pushes downward thesolder piece Wh which is left in the lower blade hole 221 after beingcut by the cutter upper blade 21 and the cutter lower blade 22. Thepusher pin 23 includes: the rod portion 231 which is slidably supportedin the pin hole 212; a head portion 232 which is provided at the endportion of the rod portion 231; and a spring 233 which is wound aroundthe rod portion 231 and which is arranged between the head portion 232and the cutter upper blade 21. Furthermore, in the pusher pin 23, at theend portion of the rod portion 231 on the side opposite to the headportion 232, a stopper for reducing the removal of the rod portion 231from the pin hole 212 is provided. The pusher pin 23 is constantlyraised upward, that is, to the side opposite to the cutter lower blade22 by the elastic force of the spring 233.

As shown in FIGS. 1 and 2, the drive mechanism 3 includes: an aircylinder 31 which is held by the holding portion 12; a piston rod 32which passes through a through hole provided in the holding portion 12and which is driven by the air cylinder 31 so as to slide in the Zdirection; and a guide shaft 35 which is supported both by the holdingportion 12 and the cutter lower blade 22, which is extended in the Zdirection and which is formed in the shape of a cylinder. The drivemechanism 3 further includes: a cam member 33 that is supported by theguide shaft 35 so as to be able to slide in the Z direction; and aslider portion 34 that includes a cam groove 340 with which a pin 332provided in the cam member 33 and described later is engaged.

The air cylinder 31 drives the piston rod 32 such that the piston rod 32slides (expands and contracts) by the pressure of air supplied from theoutside, and the air cylinder 31 and the piston rod 32 form the actuatorof the drive mechanism 3. The piston rod 32 is provided parallel to theguide shaft 35, and linearly reciprocates along the guide shaft 35. Atip end portion of the piston rod 32 is fixed to the cam member 33, andthe cam member 33 slides in the Z direction by the expansion andcontraction of the piston rod 32. The sliding of the cam member 33 isguided by the guide shaft 35.

As shown in FIG. 2, a lower end portion of the guide shaft 35 is fittedinto a concave hole provided in the cutter lower blade 22, and the guideshaft 35 is screwed and fixed to the cutter lower blade 22 with a screw351. An upper portion of the guide shaft 35 passes through a holeprovided in the holding portion 12, and the movement thereof isrestricted by a pin 352. In other words, the guide shaft 35 is fixedwith the screw 351 to the cutter lower blade 22 and is fixed with thepin 352 to the holding portion 12.

As shown in FIGS. 2 and 3, the cam member 33 is a rectangular member,and includes: a concave portion 330 that is obtained by cutting out partof a long side into a rectangular shape; and a cylindrical supportportion 331 that is coupled to the cam member 33 and that includes athrough hole through which the guide shaft 35 passes. In the concaveportion 330, the slider portion 34 is arranged slidably (in the Xdirection and the Z direction). The support portion 331 is shaped so asto extend in a direction parallel to the pin 35, and is provided so asto reduce the rattling of the cam member 33. In other words, when thecam member 33 has a certain degree of thickness, and thus it is unlikelythat rattling occurs, the cylindrical portion may be omitted such thatonly the through hole forms the support portion 331.

The cam member 33 further includes: the cylindrical pin 332 which isprovided in an intermediate portion of the concave portion 330 and whosecenter axis is perpendicular to the guide shaft 35; a pin pushingportion 333 which is adjacent to the concave portion 330 and whichpushes the pusher pin 23; and a bearing 334 which is arranged within thesupport portion 331. The pin 332 is inserted into the cam groove 340which is provided in the slider portion 34 and which will be describedlater. The bearing 334 is a member which is externally fitted to theguide shaft 35 and which makes cam member 33 smoothly slide such thatthe cam member 33 is prevented from rattling.

As shown in FIGS. 2 and 3, the slider portion 34 is a member which isformed in the shape of a rectangular plate, and is formed integrallywith the cutter upper blade 21. The slider portion 34 includes the camgroove 340 which passes through the plate in the direction of thicknessof the plate and which is extended in a longitudinal direction. The camgroove 340 includes a first groove portion 341 on the upper side whichis extended parallel to the guide shaft 35 and a second groove portion342 on the lower side which is extended parallel to the guide shaft 35.The first groove portion 341 and the second groove portion 342 areprovided so as to be displaced from each other in the X direction, andthe cam groove 340 includes a connection groove portion 343 whichconnects the first groove portion 341 and the second groove portion 342.

The pin 332 of the cam member 33 is inserted into the cam groove 340,the cam member 33 is moved along the guide shaft 35 and thus the pin 332slides on the inner surface of the cam groove 340. When the pin 332 islocated in the connection groove portion 343 of the cam groove 340, thepin 332 pushes the inner surface of the connection groove portion 343.In this way, the slider portion 34 and the cutter upper blade 21 formedintegrally with the slider portion 34 are moved (slide with respect tothe cutter lower blade 22) in a direction (X direction) intersecting thedirection of sliding of the cam member 33 (Z direction).

As shown in FIG. 2, the heater unit 4 is a heating device for heatingand melting the solder piece Wh, and is fixed to the heater unit fixingportion 14 provided in a lower end portion of the wall member 22. Theheater unit 4 includes a heater 41 which generates heat by passingelectricity and a heater block 42 for attaching the heater 41. Theheater 41 is wound around the outer circumferential surface of thecylindrical heater block 42.

The heater block 42 has a cylindrical shape, and includes: a concaveportion 421 which is used for attaching the iron tip 5 to an end portionin the axial direction and whose cross section is circular; and a soldersupply hole 422 which passes through from the center portion of a bottomportion of the concave portion 421 to the opposite side. The heaterblock 42 is provided in contact with the cutter lower blade 22 such thatthe solder supply hole 422 and the lower blade hole 221 communicate witheach other. The heater block 42 is provided as described above, and thusthe solder piece Wh is moved from the lower blade hole 221 to the soldersupply hole 422.

The iron tip 5 is a member which is formed in the shape of a cylinderextended in an up/down direction and which can be heated, and includes asolder hole 51 in a center portion which is extended in the axialdirection. The iron tip 5 is inserted into the concave portion 421 andis prevented from being removed with an unillustrated member. The solderhole 51 of the iron tip 5 communicates with the solder supply hole 421of the heater block 42, and the solder piece Wh is fed from the soldersupply hole 421.

The heat from the heater 41 is transmitted to the iron tip 5, and thesolder piece Wh is melted by the heat. Hence, the iron tip 5 is formedof a material having a high thermal conductivity, for example, a ceramicsuch as a silicon carbide or an aluminum nitride or a metal such astungsten. Although in the soldering device A, the iron tip 5 is formedin the shape of a cylinder, there is no limitation to thisconfiguration, and the iron tip 5 which is formed in the shape of a tubewhose cross section is polygonal or oval may be used. The iron tip 5 maybe prepared that has a different shape according to the wiring board Bdand (or) the shape of the terminal P of the electronic component Ep onwhich soldering is performed.

As shown in FIGS. 1 and 2, the solder feed mechanism 6 supplies the wiresolder W, and includes a pair of feed rollers 61 a and 61 b which feedthe wire solder W and a guide tube 62 which guides the fed wire solder Wto the upper blade hole 211 of the cutter upper blade 21. The pair offeed rollers 61 a and 61 b are attached to the support portion 1,sandwich the wire solder W and are rotated so as to feed the wire solderW downward. The guide tube 62 is a tubular member which can beelastically deformed, and the upper end thereof is arranged close to aportion of the feed rollers 61 from which the wire solder W is fed.

The lower end of the guide tube 62 is provided so as to communicate withthe upper blade hole 211 of the cutter upper blade 21. The lower end ofthe guide tube 62 is moved so as to follow the sliding of the cutterupper blade 21, and the guide tube 62 is provided so as not to beexcessively pulled or stick in the range of the sliding of the cutterupper blade 21. The length of the wire solder fed is determined by therotation angles (the numbers of revolutions) of the individual feedrollers 61 a and 61 b.

When the soldering is performed with the soldering device A, the tip endof the iron tip 5 is brought into contact with the land Ld of the wiringboard Bd on which the soldering is performed, and the land Ld and theterminal P of the electronic component Ep are surrounded by the iron tip5. Here, the heat from the heater 41 is transmitted to the iron tip 5,and the iron tip 5 is brought into contact with the land Ld and theterminal P of the electronic component Ep such that they are heated(preheated) to a temperature suitable for the soldering.

[Operation of Soldering Device]

The operation of the soldering device A will then be described. As shownin FIG. 2, immediately before the soldering is performed, the solderingdevice A is in a state where the piston rod 32 is stored within the aircylinder 31, and the cam member 33 is in an upper portion (the uppermostportion of the range of the sliding) in the Z direction. Here, the pin332 is located within the first groove portion 341 of the cam groove340, and the cutter upper blade 21 is located in a position closest tothe guide shaft 35. This position is assumed to be the initial position.The cutter upper blade 21 and the cutter lower blade 22 are formed suchthat when the soldering device A is in the initial position, the upperblade hole 211 and the lower blade hole 221 are overlaid on each otherin the Z direction.

Then, the feed rollers 61 a and 61 b are driven to rotate so as to feedthe wire solder W. Since the upper blade hole 211 and the lower bladehole 221 are in a state where they communicate with each other, the tipend of the wire solder W is moved into the lower blade hole 221. Therotation angles of the feed rollers 61 a and 61 b are adjusted such thatthe length of the wire solder W entering the lower blade hole 221 is thelength of the first solder piece Wh1.

In one round of the soldering, an amount of solder obtained by addingthe amount of first solder piece Wh1 and the amount of second solderpiece Wh2 is used. With consideration given to this fact, the lengths ofthe first solder piece Wh1 and the second solder piece Wh2 aredetermined according to, for example, the sizes of the land Ld and theterminal P of the electronic component Ep on which the soldering isperformed. In the present embodiment, the length of the first solderpiece Wh1 is set equal to the length of the second solder piece Wh2, andeach of the amounts of solder pieces Wh1 and Wh2 is set to the half ofthe amount of solder necessary for one round of the soldering.

Then, the piston rod 32 is protruded from the air cylinder 31, and thusthe cam member 33 is moved downward along the guide shaft 35. Since thepin 332 is arranged within the cam groove 340, the pin 332 slides withinthe cam axis 340. When the pin 332 is in the first groove portion 341,since the first groove portion 341 coincides with the direction ofmovement of the pin 332 (the axial direction of the guide shaft 35), theslider portion 34 does not receive a force from the cam member 33, andthus the cam member 34 is stationary. Then, when the pin 332 reaches theconnection groove portion 343 from the first groove portion 341, the pin332 pushes the inner surface of the connection groove portion 343. Inthis way, a force in the X direction is applied to the slider portion34, and thus the slider portion 34 and the cutter upper blade 21 formedintegrally with the slider portion 34 are moved (slide) in the Xdirection.

The cutter upper blade 21 slides such that the upper blade hole 211 andthe lower blade hole 221 are displaced in the X direction, and thus thecutting blade formed in the edge of the end portion of the upper bladehole 211 intersects the cutting blade formed in the edge of the endportion of the lower blade hole 221. Consequently, the wire solder W iscut, and thus the first solder piece Wh1 is first produced.

When the piston rod 32 is further protruded, the cam member 33 isfurther moved downward, and thus the pin 332 is moved from theconnection groove portion 343 to the second groove portion 342. Sincethe second groove portion 342 is also extended parallel to the guideshaft 35, even when the cam member 33 is moved downward along the guideshaft 35, the pin 332 does not push the slider portion 34. In otherwords, although the cam member 33 is moved, the cutter upper blade 21and the slider portion 34 are stopped. The cutter upper blade 21 islocated in a position farthest from the guide shaft 35. The cutter upperblade 21 and the cutter lower blade 22 are formed such that when thecutter upper blade 21 is in this position, the pin hole 212 is overlaidon the lower blade hole 221 in the Z direction.

When the piston rod 32 is much further protruded, the cam member 33slides downward, and thus the pin pushing portion 333 of the cam member33 pushes the head portion 232 of the pusher pin 23. In this way, therod portion 231 of the pusher pin 23 is inserted into the lower bladehole 221. Here, the first solder piece Wh1 which is left in the lowerblade hole 221 is pushed by the rod portion 231 so as to be moved towardthe iron tip 5. Although the first solder piece Wh1 may be moveddownward by its weight at the time of cutting, by the utilization of thepusher pin 23, the first solder piece Wh1 can be reliably supplied intothe solder hole 51 of the iron tip 5.

As shown in FIG. 4, the first solder piece Wh1 supplied into the solderhole 51 is held in a state where the first solder piece Wh1 is erectedwithin the iron tip 5 so as to ride on the terminal P of the electroniccomponent Ep. Furthermore, in the soldering device A, as in the case ofthe first solder piece Wh1, the wire solder W is cut again, and thus thesecond solder piece Wh2 is produced at this time. The second solderpiece Wh2 is also supplied into the solder hole 51 of the iron tip 5 bythe utilization of the pusher pin 23 (or by its weight).

Consequently, as shown in FIG. 5, within the iron tip 5, the solderpieces Wh1 and Wh2 are in a state where they are erected such that thesecond solder piece Wh2 rides on the first solder piece Wh1. Asdescribed above, the soldering device A supplies the first solder pieceWh1 and the second solder piece Wh2 in this order from above into theiron tip 5. The inside diameter of the iron tip 5 is set so as to beslightly larger than the outside diameter of each of the solder piecesWh1 and Wh2. Hence, even when the solder pieces Wh1 and Wh2 are inclinedwithin the iron tip 5, they are supported by the inner wall thereof soas to be erected within the iron tip 5 without fail.

The heat from the heater 41 is transmitted to the iron tip 5, and thefirst solder piece Wh1 and the second solder piece Wh2 are heated by theheat. Here, as shown in FIG. 6, the flux 72 which flows out from thelower end portion of the second solder piece Wh2 flows between the firstsolder piece Wh1 and the inner wall surface of the iron tip 5. The flux72 has, for example, as a main component, a rosin which is melted atabout 70° C. It is known that the thermal conductivity of a rosin issufficiently (about 10 times) larger than that of air.

Since the flux 72 flowing therebetween serves as a heat medium (whichmakes it easy to transmit the heat from the iron tip 5 to the firstsolder piece Wh1), as compared with a case where the flux 72 does notflow therebetween, the first solder piece Wh1 is melted rapidly andreliably. For example, the flux 72 has a lower melting point than thesolder, the second solder piece Wh2 is closer to the heater unit 4 thanthe first solder piece Wh1 and thus the flux 72 flows out from thesecond solder piece Wh2 in a relatively early stage. Even when the flux72 of the second solder piece Wh2 flows out from the upper end portionof the second solder piece Wh2 or from the upper end portion and thelower end portion thereof, the flux 72 likewise serves as the heatmedium, and thus the first solder piece Wh1 is melted rapidly andreliably. However, it is likely that when the flux 72 flows out from theupper end portion of the second solder piece Wh2, the second solderpiece Wh2 is melted earlier than the first solder piece Wh1, the moltensecond solder piece Wh2 flows between the first solder piece Wh1 and theinner wall surface of the iron tip 5 and this serves as the heat medium,with the result that the melting of the first solder piece Wh1 ispromoted. Through the process described above, finally, both the firstsolder piece Wh1 and the second solder piece Wh2 are completely heatedand melted so as to be supplied onto the wiring board Bd arranged below.

Since the iron tip 5 surrounds the land Ld of the wiring board Bd andthe terminal P of the electronic component Ep, the molten solder flowsto the land Ld and the terminal P of the electronic component Eparranged below. Then, the soldering device A is moved in the Zdirection, and thus the iron tip 5 is moved away from the land Ld. Inthis way, the solder is cooled by outside air so as to be solidified,and thus the land Ld and the terminal P of the electronic component Epare soldered.

Then, when the soldering is completed, the air cylinder 31 stores thepiston rod 32 thereinto. In this way, the cam member 33 is moved upwardin the Z direction, and the pusher pin 23 is pushed upward by theelastic force of the spring 233. The rod portion 231 is removed from thelower blade hole 221. Even if the cutter upper blade 21 slides in thisstate, the pusher pin 23 is not broken. Then, the pin 332 of the cammember 33 reaches the connection groove portion 343 of the cam groove340, and the slider portion 34 and the cutter upper blade 21 slide so asto approach the guide shaft 35. When the pin 332 reaches the firstgroove portion 341 of the cam groove 340, the soldering device A isreturned to the initial position.

2. Second Embodiment

The second embodiment will then be described. The second embodiment isbasically the same as the first embodiment except the lengths of thesolder pieces. In the following description, emphasis is placed on thedescription of portions which differ from those in the first embodiment,and the description of the common portions may be omitted.

The soldering device A of the second embodiment cuts the wire solder Wsuch that the second solder piece Wh2 is shorter than the first solderpiece Wh1. Specifically, in the present embodiment, the wire solder W isfed out by the solder feed mechanism 6 such that the second solder pieceWh2 is shorter than the first solder piece Wh1, and the wire solder Wfed out is cut by the cutter unit 6. The total of the amount of firstsolder piece Wh1 and the amount of second solder piece Wh2 is adjustedsuch that the total is the amount of solder necessary for one round ofthe soldering.

FIG. 7A shows a state where the first solder piece Wh1 is first suppliedinto the iron tip 5 so as to ride on the terminal P of the electroniccomponent Ep. FIG. 7B shows a state where the second solder piece Wh2 isfurther supplied so as to ride on the first solder piece Wh1. FIG. 7Cshows a state where in the state shown in FIG. 7B, a certain amount oftime has elapsed such that the flux 72 flows out from the second solderpiece Wh2.

As shown in FIG. 7B, in the present embodiment, the second solder pieceWh2 is shorter than the first solder piece Wh1, and within the iron tip5, these solder pieces are erected such that the second solder piece Wh2rides on the first solder piece Wh1. Even in the present embodiment, theinside diameter of the iron tip 5 is set so as to be slightly largerthan the outside diameter of each of the solder pieces Wh1 and Wh2.Hence, even when the solder pieces Wh1 and Wh2 are inclined within theiron tip 5, they are supported by the inner wall thereof so as to beerected within the iron tip 5 without fail.

Furthermore, in the present embodiment, the second solder piece Wh2 isshorter than the first solder piece Wh1, and accordingly, the heatcapacity is relatively low. Hence, in the present embodiment, ascompared with the first embodiment, the second solder piece Wh2 iseasily increased in temperature, and thus as shown in FIG. 7C, the flux72 flows out from the second solder piece Wh2 in an earlier stage.

In this way, in the present embodiment, the first solder piece Wh1 canbe melted more rapidly and reliably. The temperature increase of thesecond solder piece Wh2 is sped up as the second solder piece Wh2 isproduced so as to be shorter (as the heat capacity is decreased). Withrespect to the specific lengths of the solder pieces, for example, thelength of the first solder piece Wh1 is set to 15 mm, the length of thesecond solder piece Wh2 is set to 2 mm and thus it is possible tosufficiently obtain the effects of the present invention.

In terms of enhancing the efficiency of heating of the solder piece, thedifference between the inside diameter of the iron tip 5 and the outsidediameter of the solder piece is preferably minimized. However, anappropriate clearance is preferably provided between the iron tip 5 andthe solder piece so that the supply of the solder piece into the irontip 5 is not prevented by burrs resulting from the cutting of the solderpiece or the deformation of the solder piece. In the present embodiment,with consideration given to what has been described above, the insidediameter of the iron tip 5 is set within a range of 0.7 to 2.3 mm, theoutside diameter of the solder piece is set within a range of 0.6 to 1.2mm and the difference between the inside diameter and the outsidediameter is set within a range of 0.2 to 1.1 mm.

3. Third Embodiment

The third embodiment will then be described. The third embodiment isbasically the same as the first embodiment except the lengths of thesolder pieces and the internal shape of the iron tip. In the followingdescription, emphasis is placed on the description of portions whichdiffer from those in the first embodiment, and the description of thecommon portions may be omitted.

The soldering device A of the third embodiment cuts the wire solder Wsuch that the first solder piece Wh1 is shorter than the second solderpiece Wh2. Specifically, in the present embodiment, the wire solder W isfed out by the solder feed mechanism 6 such that the first solder pieceWh1 is shorter than the second solder piece Wh2, and the wire solder Wfed out is cut by the cutter unit 6. The total of the amount of firstsolder piece Wh1 and the amount of second solder piece Wh2 is adjustedsuch that the total is the amount of solder necessary for one round ofthe soldering.

FIG. 8 shows a state where the first solder piece Wh1 is supplied intothe iron tip 5. As shown in the figure, in the third embodiment, withinthe iron tip 5, a reception portion which receives the supplied firstsolder piece Wh1 is provided. More specifically, the reception portionis a step 5 s which is protruded inward from the inner walls of the irontip 5 such that the inside diameter of the iron tip 5 is less than theoutside diameter of the first solder piece Wh1. The inside diameter ofthe iron tip 5 is slightly larger than the outside diameter of the firstsolder piece Wh1 on the upper side with respect to the step 5 s whereasthe inside diameter of the iron tip 5 is slightly smaller than theoutside diameter of the first solder piece Wh1 on the lower side withrespect to the step 5 s.

The step 5 s within the iron tip 5 is provided in a position on theupper side with respect to the tip end of the terminal P of theelectronic component Ep. Hence, when the first solder piece Wh1 issupplied into the iron tip 5, as shown in FIG. 8, the first solder pieceWh1 is caught on the step 5 s within the iron tip 5 before reaching theterminal P, and thus the first solder piece Wh1 can be brought into astate where the first solder piece Wh1 is erected on the step 5 s(reception portion).

FIG. 9 shows a state where in the state of FIG. 8, the second solderpiece Wh2 is further supplied. As shown in FIG. 9, in the presentembodiment, the first solder piece Wh1 is shorter than the second solderpiece Wh2, and within the iron tip 5, the solder pieces are erected suchthat the second solder piece Wh2 rides on the first solder piece Wh1.The inside diameter of the iron tip 5 on the upper side with respect tothe step 5 s is set so as to be slightly larger than the outsidediameter of each of the solder pieces Wh1 and Wh2. Hence, even when thesolder pieces Wh1 and Wh2 are inclined within the iron tip 5, they aresupported by the inner wall thereof so as to be erected within the irontip 5 without fail.

Furthermore, the first solder piece Wh1 in the present embodiment issupplied into the iron tip 5 earlier than the second solder piece Wh2,and the first solder piece Wh1 is shorter than the second solder pieceWh2, and accordingly, the heat capacity is relatively low. Thus, in thepresent embodiment, the first solder piece Wh1 is increased intemperature more easily than the second solder piece Wh2.

Hence, when the iron tip 5 is heated in the state shown in FIG. 9, asshown in FIG. 10, the flux 72 is melted out from the first solder pieceWh1, and the solder 71 is melted. Consequently, heat conduction to thesecond solder piece Wh2 is performed through the flux 72 melted out fromthe first solder piece Wh1 and the molten solder 71, and thus togetherwith the first solder piece Wh1, the second solder piece Wh2 can beheated and melted more rapidly and reliably.

4. Others

The soldering device A of each of the embodiments described aboveincludes: the substantially tubular iron tip 5 that can be heated andthat is extended vertically; and a functional portion (solder piecesupply portion) that supplies the first solder piece Wh1 and the secondsolder piece Wh2 in which the layer of the flux 72 is provided withinthe layer of the tubular solder 71 in this order from above into theiron tip 5. In the soldering device A, within the iron tip 5, the solderpieces are erected such that the second solder piece Wh2 rides on thefirst solder piece Wh1, the heat of the iron tip 5 is used to melt thefirst solder piece Wh1 and the second solder piece Wh2 and thus themolten solder is supplied downward.

Hence, with the soldering device A, it is possible to more reliably heatand melt the solder pieces in a posture where they are erected withinthe iron tip 5. The solder piece supply portion included in thesoldering device A can also sequentially produce the first solder pieceWh1 and the second solder piece Wh2 by cutting the wire solder W.

The soldering device A of each of the first embodiment and the secondembodiment solders, to the wiring board Bd, the terminal P of theelectronic component Ep protruded upward. Then, the soldering device Asupplies the solder pieces in a state where the tip end of the terminalP enters the iron tip 5 from below, and thereby brings the first solderpiece Wh1 into a state where the first solder piece Wh1 is erected onthe tip end of the terminal P. In the case of the second embodiment, thesolder piece supply portion cuts the wire solder W such that the secondsolder piece Wh2 is shorter than the first solder piece Wh1.

On the other hand, within the iron tip 5 in the soldering device A ofthe third embodiment, the reception portion for receiving the suppliedfirst solder piece Wh1 is provided, and thus the first solder piece Wh1can be brought into a state where the first solder piece Wh1 is erectedon the reception portion. Although in the present embodiment, as thespecific form of the reception portion, the step 5 s is adopted which isprotruded inward from the inner walls of the iron tip 5, another formmay be adopted. The solder piece supply portion cuts the wire solder Wsuch that the first solder piece Wh1 is shorter than the second solderpiece Wh2.

Although the embodiments of the present invention have been describedabove, the present invention is not limited to the details thereof. Inthe embodiments of the present invention, various variations can beadded without departing from the spirit of the invention.

REFERENCE SIGNS LIST

-   -   A soldering device (solder processing device)    -   1 support portion    -   11 wall member    -   12 holding portion    -   13 sliding guide    -   14 heater unit fixing portion    -   15 actuator holding portion    -   16 spring holding portion    -   2 cutter unit    -   21 cutter upper blade    -   211 upper blade hole    -   212 pin hole    -   22 cutter lower blade    -   221 lower blade hole    -   23 pusher pin    -   231 rod portion    -   232 head portion    -   233 spring    -   3 drive mechanism    -   31 air cylinder    -   32 piston rod    -   33 cam member    -   330 concave portion    -   331 support hole    -   332 pin    -   333 pin pushing portion    -   334 bearing    -   34 slider portion    -   340 cam groove    -   341 first groove portion    -   342 second groove portion    -   343 connection groove portion    -   35 guide shaft    -   4 heater unit    -   41 heater    -   42 heater block    -   421 concave portion    -   422 solder supply hole    -   5 iron tip    -   5 s step    -   51 solder hole    -   6 solder feed mechanism    -   61 a, 61 b feed roller    -   62 guide tube    -   71 solder    -   72 flux    -   P terminal    -   W wire solder    -   Wh solder piece    -   Wh1 first solder piece    -   Wh2 second solder piece    -   Bd wiring board    -   Ep electronic component    -   Ld land

The invention claimed is:
 1. A solder processing method, comprisingsequentially supplying at least two solder pieces, each of whichincludes a tubular solder layer and a layer of a flux provided withinthe tubular solder layer, into a substantially tubular iron tip that isextended vertically, such that the at least two solder pieces areerected within the substantially tubular iron tip in such a manner thaton the solder piece which is first supplied, the solder piece which issubsequently supplied rides, and heating the substantially tubular irontip in a state where the at least two solder pieces are erected withinthe substantially tubular iron tip in such a manner that on the solderpiece which is first supplied, the solder piece which is subsequentlysupplied rides, to melt the flux to be flown out from at least one ofthe at least two solder pieces to a space between an inner wall of thesubstantially tubular iron tip and the at least two solder pieces,thereby enhancing contactability between the inner wall of thesubstantially tubular iron tip and the at least two solder pieces, tomelt the at least two solder pieces such that a molten solder issupplied downward from the substantially tubular iron tip, whereinsequentially supplying the at least two solder pieces comprises cuttinga wire solder to sequentially produce a first solder piece and a secondsolder piece as the at least two solder pieces to thereby sequentiallysupply the first and second solder pieces into the substantially tubulariron tip, and subsequently supplying of the first and second solderpieces is performed in a state where a tip end of a terminal protrudedupward from a board enters the substantially tubular iron tip from belowso that the first solder piece is to be erected on the tip end of theterminal.
 2. The solder processing method according to claim 1, whereincutting the wire solder comprises cutting the wire solder such that thesecond solder piece is shorter than the first solder piece.
 3. Thesolder processing method according to claim 1, wherein cutting the wiresolder comprises cutting the wire solder such that the first solderpiece differs in length from the second solder piece.